Currently, various types of projector capable of forming images by modulating light emitted from a light source and projecting the images on a screen or the like, which projector particularly includes a microcomputer (calculation processing circuit) in a light source drive device (discharge lamp lighting device) for actuating the light source have been proposed, for example, with Japanese Patent Publication No. 2005-243381). According to these types of projector, a main control device of the projector performs various controls over the light source and obtains various information from the light source drive device with high accuracy through communication with the microcomputer of the light source drive device.
According to the projector having this structure, however, there is a possibility that communication between the control device and the microcomputer cannot be achieved in normal condition due to effect of external noise or the like, or that normal control over the light source drive device cannot be performed when unexpected faulty operation is caused by the microcomputer.